Reflection liquid crystal display devices have been used for portable cellular phones or intelligent terminals. The reflection liquid crystal display devices do not require any back light used for a light source since an externally entered incident light is reflected by a reflector disposed within the device and a reflected light is used as a display illumination light. As a result, the reflection type liquid crystal display devices are more effective to achieve reduction in power consumption, thickness and weight as compared with a transmitting type liquid crystal display device.
The structure of the reflection type liquid crystal display device mainly comprises a liquid crystal cell using TN (twisted nematic), one sheet polarization plate type, STN (supertwisted nematic)type, GH (guest host) type, PDLC (polymer dispersion) type, cholesteric type; elements for switching the liquid crystal cells and a reflector which is disposed internally or externally of the liquid crystal cell.
Such reflection type liquid crystal display devices can provide high definition and high quality images by adopting an active matrix drive system using thin film transistors or metal/dielectric film/metal structure diodes as transistors.
Provision of a reflector having optimal reflection characteristics is effective to increase the strength of light scattered in a direction normal to the display screen for light incident from a wide range of angles, so that brighter display can be obtained.